Antimicrobial polymers comprising quaternary ammonium groups, their use for making a material with antimicrobial properties and methods for preparing them

ABSTRACT

The invention relates to antimicrobial non-cross-linked polymers which are constituted of an ester and/or amide resin to which quaternary ammonium salts are bound by a covalent bond which is potentially reactive with water, the quaternary ammonium content being at least 1 M/kg, a well as to the use thereof for the preparation of a material having antimicrobial properties and to their methods of preparation.

BACKGROUND OF THE INVENTION

The invention relates to antimicrobial non-cross-linked polymers whichcomprise quaternary ammonium groups bound via a bond which ispotentially reactive with water, and which have an antimicrobialactivity, especially an antibacterial activity.

The invention also relates to their methods of preparation as well as totheir applications, especially in a non-limiting manner, for obtainingantibacterial materials having self-smoothening, self-sliding oranti-static properties or as binders for coatings or paints.

Obtaining polymers which comprise quaternary ammonium groups isdescribed in a certain number of patents or patent applications.

WO 95/27473 describes a polymer having a carbon skeleton, whichcomprises quaternised nitrogen atoms, one of the substituents of whichis hydrophobic and has at least eight carbon atoms, and having anantiperspirant activity.

DE 4 242 082 describes copolymers of acrylamide or methacrylamide whichcomprise quaternary ammonium groups the content of which must not exceed20% of the mass of the final product.

EP 0 611 782 describes a homo- or copolymer which contains antimicrobialquaternary ammonium groups, but which comprise, between the polymerchain and the active group, one or more silicon-carbon or silicon-oxygenbonds which give the final product its particular properties.

WO 91/09915 describes an anti-fouling composition which is constitutedof a hydrolysable binder, and which contains sulphonic acid groups andquaternary ammonium salts (the latter two being bound by an ionic andnon-covalent bond).

EP 0 270 465 relates to quaternary ammoniums which are grafted onto achlorinated vinylic resin by a non-hydrolysable or non-water sensitivebond.

EP 0 156 632 describes a copolymer which comprises acrylic ormethacrylic esters which can optionally contain quaternary ammoniumfunctions, and which contain organotin compounds which are introduced bycopolymerisation, in a submarine anti-fouling paint application.

WO 84/02915 describes polymers comprising acrylic or methacrylic esterscomprising units which are able to be hydrolysed and optionally able tocontain quaternary ammonium functions, in a submarine anti-marking paintapplication.

Other publications, notably EP 0 494 554, EP 0 657 478, and EP 0 373852, relate to quaternary ammoniums (mainly having a short chain of lessthan 4 carbons) bound to an acrylic skeleton. However, these documentsdescribe products which are cross-linked and sometimes copolymerisedwith other vinylic monomers. In every case, the quaternary ammoniumcontent is low.

SUMMARY OF THE INVENTION

It has now been found that polymers comprising quaternary ammoniums in apredominant amount possess an anti-microorganisms activity, inparticular an antibacterial activity, which is optimal. Moreover, due tothe potentially hydrolysable nature of the bond (of the amide or estertype) of the quaternary ammonium groups with the resin, they aresusceptible of conferring a self-regenerating nature to the materials orcoatings which contain them.

DETAILED DESCRIPTION OF THE INVENTION

According to a first aspect, therefore, the invention relates tonon-cross- linked polymers, characterised in that they are constitutedof an ester and/or amide resin to which quaternary ammonium salts arebound by a covalent bond which is potentially reactive with water, andin which the quaternary ammonium content is at least 1 mole/kg,preferably at least 2 moles/kg and in particular at least 3 moles/kg,for the use thereof as antimicrobial agents, notably as antibacterialagents.

In a preferred aspect, the weight percentage of quaternary ammoniumsalts is at least 80%, and advantageously up to 100% of the mass of thepolymer.

In a particular aspect therefore, the invention relates tonon-cross-linked polymers, characterised in that they are constituted ofan ester and/or amide resin, to which quaternary ammonium salts arebound by a covalent bond which is potentially reactive with water, ofgeneral formula (I):

in which:

A represents a

function,

and/or an amide function:

R represents H or CH₃;

B represents a C₀-C₅ alkylene chain, which is linear or branched, or anarylene or arylalkylene group;

R₁ and R₂, which are identical or different, each represent a C₁-C₅alkyl chain

R₃ represents a C₈-C₂₀ alkyl chain or an aryl or arylalkyl group

X⁻ represents an anion

in which polymers the quaternary ammonium content is at least 1 mole/kg.

According to another aspect, the invention relates to non-cross-linkedpolymers, characterised in that they are constituted of an ester and/oramide resin to which quaternary ammonium salts are bound by a covalentbond which is potentially reactive with water, of general formula (II):

in which

A represents a

function, and/or an amide function:

R represents H or CH₃;

B represents a C₀-C₅ alkylene chain, which is linear or branched or anarylene or arylalkylene group;

W⁺ is a saturated or unsaturated heterocycle comprising a nitrogen atomsubstituted with R₄, or directly bound to A or to B, and also able tocontain, in addition to the quarternised nitrogen, one or moreheteroatoms, which are identical or different,

R₄ represents a C₁-C₂₀ alkyl chain or an aryl or aralkyl group;

X⁻ represents an anion;

in which polymers the quaternary ammonium content is more than 1 mole/kg

Preferably, the total number of atoms of the heterocycle constituting W⁺is 3 to 15.

Advantageously, W⁺ comprises a heterocycle selected from piperidine,piperazine, morpholine, thiomorpholine or thiazole, isothiazole,pyrazole, indole, indazole, imidazole, benzimidazole, quinoline,isoquinoline, benzotriazole, benzothiazole, benzoisothiazole,benzoxazole, benzoxazine, isoxazole, pyrrole, pyrazine, pyrimidine,pyridazine, quinazoline, acridine, one or more double bonds of which canbe hydrogenated, it being possible for said groups to be non-substitutedor substituted once or more, for example, in a non-limiting manner, witha substituent selected from the following groups: alkyl, halogen, cyano,nitro, hydroxy, sulphone, trifluoromethyl.

When B represents an arylene or arylalkylene group and/or R₃ is an arylor arylalkyl group, the aromatic ring can for example be a phenyl groupand the alkyl chain can be a C₁-C₅ alkyl chain.

According to an advantageous aspect, the invention relates tonon-cross-linked polymers, characterised in that they are constituted ofan ester and/or amide resin to which quaternary ammonium salts are boundby a covalent bond which is potentially reactive with water, comprisingboth units of formula (I) and (II) as defined above.

Advantageously, the polymers of formulae (I) and/or (II) above comprisea weight percent of quaternary ammonium salts of at least 80%,advantageously up to 100 % of the mass of the polymer.

This total weight percentage comprises the ester or amide functions aswell as the mixture of the two types of functions.

In a preferred aspect, the quaternary ammonium content is greater thanor equal to 2 moles/kg and notably greater than or equal to 3 moles/kg.

The anion X⁻¹ is selected from the anions which are usually used in thefield and which are well-known to the person skilled in the art, suchas, for example, in a non-limiting way, halogen, sulphate, phosphate,nitrate, cyano, tosylate or metal anions or organic anions, such as, forexample, salicylate, benzoate, alkoxide, acetate, or undecylenate.

The invention also relates to the polymers of formulae (I) and/or (II)as defined above, for the use thereof as antimicrobial agents, notablyas antibacterial agents.

According to a further aspect, the invention also relates to the use ofthe polymers described above, in particular of the polymers of formulae(I) and/or (II) for preparing proper objects with said polymers, inparticular in the medical field for the preparation of medical materialssuch as, for example, catheters, gastric probes, blood collectionpouches or even slabs for the ground, soles, tiling joints, or anyobject or material of which it is desirable to possess antimicrobialproperties, notably antibacterial properties.

The invention also relates to the use of the polymers described above,in particular of the polymers of formulae (I) andlor (II) for thepreparation of paints, not only marine paints, but also for white roomsfor example, or even facade coatings, i.e. anywhere in fact where thereare risks of development of microorganisms, and in particular bacteria,against which it is desired to protect oneself.

More particularly, the invention relates to paints or coatings whichcomprise, as a binder, at least one polymer described above, inparticular at least one polymer of formulae (I) and/or (II), incombination with a volatile support. For this application, the polymersaccording to the invention are used in combination with the usualcomponents of paints such as solvents in particular, for example analcohol ether, xylene or cyclohexane, and pigments such as, for example,barium sulphate, titanium oxide or iron oxide.

The bond which is potentially reactive with water, i.e. hydrolysable,between the quaternary ammonium groups and the resin of the polymersaccording to the invention, presents an additional interest insofar asit enables the regeneration, layer by layer, of any material based onthe polymer of formulae (I) and/or (II), whether it is presented in theform of a coating or as a constituting element of said material.

The invention also relates therefore to the use of the polymers offormulae (I) and/or (II) for the preparation of self-regeneratingmaterials.

The invention also relates to the methods of preparation of the polymersdescribed above.

2 main methods of preparation are characterised:

route 1) the modification of a polymer or of a copolymer by reactionwith an alkyl halide;

route 2) the polymerisation or the copolymerisation of a monomercomprising a quaternary ammonium group.

The monomers which can be used to obtain the polymers of formula (I) inone or the other of the preparative routes, either with the view totheir polymerisation or copolymerisation before quaternisation, or withthe view to their prior quaternisation, are preferably selected fromacrylates, methacrylates, ethylmehacrylate, ethyl methacrylates, butylmethacrylates, 2-ethylhexyl methacrylates, methoxyethyl methacrylates,acetates, acrylamides, methacrylamides, maleic anhydride and vinylalcohol.

Monomers of the methacryloyl- or acryloylpyrazole type, which are knownin the field, such as those described for example in Macromol. Chem.,186, 1985, 1605-161 1, will be used to obtain the polymers of formula(II).

According to a first variant of route 1 (route 1a), the chemicalmodification is carried out in one step on a polyacrylate-type polymercomprising a tertiary amine function such as, for example,2-dimethylaminoethyl polymethacrylate or poly(3-dimethylarinopropylmethacrylamide). These precursors are obtained by methods ofpolymerisation which are known in the field. After dissolution of thesepolymers in polar-type solvents, such as, for example, methanol,propylene glycol monomethyl ether or a water/acetone mixture, thetertiary amine functions can be quaternised by an alkyl halide accordingto Scheme 1a below, in which A, B, R₁, R₂ and R₃ are as defined informula (I) and X represents a halogen atom:

The alkyl halide represented by R₃X comprises a long carbon chain whichis linear or substituted with an aromatic ring, such as, for example,octyl, lauryl or benzyl bromide.

Route 1a can also be used for preparing the polymers of formula (II), bystarting from a polyacrylate-type polymer comprising a tertiary aminefunction of formula:

in which W represents a saturated or unsaturated heterocycle comprisinga nitrogen atom, which may also contain, in addition to the nitrogen,one or more heteroatoms, which are identical or different.

In this case, the alkyl halide is represented by the formula R₄X, inwhich R₄ is as defined above for the formula (II).

The concentration of the initial polymer depends upon its weightmolecular mass, which is between about 50,000 and about 100,000, and ingeneral varies from 1 to 50% with respect to the whole of the solution,including the solvent. The concentration of alkyl halide is a functionof the ammonium content desired and varies from 1 to 100% with respectto the number of moles of quaternisable tertiary amine. The reactionyields are of the order of 100% (calculated by coulometricdeterminations).

According to a 2nd variant of route 1 (route 1b), the chemicalconversion can generally be carried out from poly(methylmethacrylate)-(PMMA)-type polymer by a transesterification with analkanolamine which is quaternised beforehand. According to the reactionscheme 1b above in which B, R, R₁, R₂, R₃ and X are as defined informula (I). The polymer is dissolved in a ketonic solvent such as, forexample, methyl ethyl ketone, methyl isoamyl ketone or methyl isobutylketone at a concentration ranging from 1 to 50%. The quaternisedethanolamine is added in the cold with a catalyst such as, for example,dioctyl tin oxide.

The solution is heated for 10 hours at 100° C. and the methanol formedis removed wit the aid of a Dean Stark-type apparatus. At the end of theexperiment, a product is collected of which the ammonium content (perunit) is close to 100% according to the initial ratios.

According to a third variant of route 1 (route 1c), the chemicalconversion can be carried out by esterification on poly(acrylic acid).This polymer is dissolved in the already-quaternised alkanolamine towhich a reaction catalyst such as sulphuric acid for example, is addedand a solvent such as toluene or cyclohexane which enables the waterformed to be removed.

This variant is represented by the reaction scheme 1c below, in which B,R₁, R₂, R₃ and X are as defined in formula (I) and R═H.

After 5 hours of azeotropic distillation at 130° C., a very viscousmixture is recovered (the weight molecular mass of which is greater thanabout 100,000) to which tetrahydrofuran is added. The fully quaternisedpolymer precipitates.

A fourth variant of route 1, which enables compounds of formula (I) tobe obtained in which B, R₁, R₂ and R₃ are as defined above in formula(I) and R═H, consists in allowing a polyalcohol such as poly(vinylalcohol) to react with a halogenated acid anhydride, notably achlorinated acid anhydride, and then in allowing the ester functionbearing the halogen atom to react with a tertiary amine to give thequaternary ammonium.

As indicated above, the second method of obtaining the polymers offormula (I) according to the invention comprising quaternary ammoniumsalts is the polymerisation of monomers comprising quaternary ammoniums,either in an organic solvent phase (route 2a), or in an aqueous phase(route 2b).

The monomers comprising quaternary ammoniums are firstly prepared bymixing, in an equimolecular amount, an amine of the methacrylic type ormethacrylamide with an alkyl halide as defined above. The reactiontemperature is maintained around 100° C. (the reaction is in homogeneousphase if an organic solvent is used, while initially it is heterogeneousif it is water). The pure product is recovered by evaporation of thesolvent and recrystallised in the hot from tetrahydrofuran.

The polymerisation of the monomers comprising quaternary ammoniums canbe carried out in an organic solvent phase by emulsion or solution(route 2a): in this case, azobisisobutyronitrile (AIBN) is added to theresulting product and heat is given at a temperature between about 20°C. and 200° C., preferably about 80° C. .

After 4 hours of reaction, the viscosity of the mixture very muchincreases and the solution is cooled to ambient temperature. The polymercan be used as such in a paint formulation.

When the polymerisation is carried out in an aqueous phase in solutionor emulsion (route 2b), the monomers comprising quaternary ammoniums,which are soluble in water, are polymerised either by the addition ofperoxide, such as, for example, AIBN or benzoyl peroxide, or with theaid of a redox-type initiator according to techniques which are known inthe field, by heating at a temperature between about 20° C. and 120° C.Polymers having high weight molecular masses (≧100,000) can be obtained.

The resulting polymer precipitates and is then cooled and dried or, ifit is desired to recover the polymer in an organic phase to use itdirectly in a paint formulation, the water can be removed by theaddition of an azeotropic solvent such as an alcohol ether, e.g.monopropylene glycol monomethyl ether.

Reaction scheme 2 below, in which R, R₁, R₂, R₃, A, B and X are asdefined above for formula (I), generally represents the 2n method ofobtaining polymers of formula (I), namely quaternisation of the monomersand polymerisation.

This reaction scheme can also be applied for the preparation of thepolymers of formula (II), by starting with monomers of formula:

in which W is as defined above.

The invention is illustrated by the Examples below.

EXAMPLE 1

Chemical Modification of a Poly(2-dimethylaminoethyl Methacrylate)(Route 1a)

18.86 g (i.e. 0.132 mole) of poly(2-dimethylaminoethyl methacrylate) areintroduced into a two-necked flask equipped with a condenser and amagnetic stirrer. 12.7 g (0.066 mole) of bromooctane and 36 g of acetoneare then added. After 18 hours at 70° C., 30 g of propylene glycolmonomethyl ether are then added and the acetone is distilled off. Thefinal product is then produced with a dry extract of 51% which is readyto use in a marine paint formulation. A coulometric determination (aswell as an analysis by infrared spectroscopy) indicates the presence of2.03 moles of ammonium/kg of dry product.

EXAMPLE 2

Esterification of Poly(Acrylic Acid) (Route 1c)

20 g of ethanolamine (quatemised beforehand with bromooctane) areintroduced in the cold with 5.1 g of poly(acrylic acid) (35% in water,the number molecular mass of which is 1,000 g/mole) into a 100 mltwo-necked flask equipped with an azeotropic distillation apparatus(Dean Stark type) and a magnetic stirrer. 30 g of toluene and 1 ml ofconcentrated sulphuric acid are added to this mixture. The solution isthen heated at 130° C. for 3 hours in which time 4 cm³ of water arecollected.

After cooling, the polymer is recovered by precipitation in ether. Themass obtained (9 g) is analysed by infrared spectroscopy which indicatesthe presence of an ester carbonyl at 1730 cm⁻¹, i.e. 2.82 moles ofammonium/kg of dry product.

EXAMPLE 3

Modification of the Monomer and then Polymerisation in Organic Phase(Route 2a)

200 g of 2-dimethylaminoethyl methacrylate are added to 246 g ofbromooctane in 450 g of propylene glycol monomethyl ether in a 3 literreactor. After 3 hours of reaction at 80SC, a coulometric determinationenables verifying a conversion rate of 100% into chloride ions. Thequaternised monomer is then either purified by a precipitation inhexane, or used for a further step (polymerisation).

2 g of azobisisobutyronitrile are added to the solution resulting fromthe preceding step, and the temperature is allowed to riseprogressively. After I hour 45 minutes (i.e. at a temperature of 76°C.), an increase in the viscosity is noted the reaction is then kept atthis temperature for 3 hours. After cooling, a binder for paint isobtained the dry extract of which is 50%, i.e. 2.75 moles ofammoniumn/kg of dry product.

EXAMPLE 4

Modification of the Monomer and then Polymerisation in Aqueous Phase(Route 2b)

400 g of 2-dimethylaminoethyl methacrylate are added to 500 g ofbromooctane and 200 g of water in a 3 liter reactor. At the start, thereaction medium which is heterogeneous is heated at 90° C. and thereaction is monitored by coulometric determination. After 4 hours ofreaction, the conversion rate into chloride ions is 100% (the reactionphase is limpid and homogeneous). The product is cooled and can be usedfor the polymerisation.

400 g of a 1% aqueous solution of gum Arabic and 5 g ofazobisisobutyronitrile are added to the aqueous solution of thepreceding step. The mixture is brought to 80° C. After 1 hour ofreaction, the viscosity of the mixture very much increases and aprecipitate appears. After 2 hours at this temperature, the reactor iscooled to about 30° C. and the polymer which forms in the form of awhitish paste is dried under vacuum. After one week of drying, a whitesolid is obtained the analysis of which by infrared spectroscopyconfirms the disappearance of the double bonds of the initial monomerand the presence of 2.75 moles of ammonium/kg of dry product. Theproduct can then be dissolved in an organic solvent in order to obtain abinder for marine paint.

EXAMPLE 5

Preparation of a Polymer of Formula (II)

1) Preparation of the Monomer:

5 g of methacryloyl chloride (0.048 mole) are mixed with 100 ml ofmethyl ethyl ketone (MEK) in a 250 ml three necked flask equipped withstirring and a condenser. A solution of 4.8 g of 2-aminothiazole (0.048mole) in 50 ml of MEK are added dropwise under mechanical stirring. Atthe end of the addition, the solution is heated at 60° C. for 4 hours.After cooling, 50 ml of basic water (sodium hydrogen carbonate) areadded so as to neutralise the hydrochloric acid formed. 7.5 g of2-thiazolylmethacrylamide are recovered after evaporation.

2) Modification of the Monomer and then Polymerisation (Route 2a)

5 g (0.030 mole) of 2-thiazolylmethacrylamide obtained in step 1) areadded to 14 g of propylene glycol monomethyl ether and 4.26 g (0.030mole) of iodomethane in a 100 ml two-necked flask equipped with amagnetic stirrer and a condenser. After 10 hours of reaction at 60° C.,a coulometric determination indicates a conversion rate of 100% intoiodide ions. The quaternised monomer is then either purified byprecipitation in hexane, or used for the polymerisation step.

0.06 g of azobisisobutyronitrile are added to the solution obtainedabove under mechanical stirring, and the temperature is allowed to riseprogressively to 85° C. After 4 hours at this temperature, an increasein the viscosity of the mixture is noted. After cooling the solution, abinder is obtained with a dry extract of 40% which is ready to use for apreparation of paint. The polymer can also be precipitated in pentane soas to obtain a polymer having an ammonium content of 3.22 moles/dry kg.

EXAMPLE 6

Study of the Antibacterial Properties of the Polymers According to theInvention

The principle of determination is the placing of the resin which is ahomopolymer having 100% quaternary ammoniums per constitutive unit (on afixed surface) in contact with an known innoculum of a bacterial orfungal strain (Staphylococcus aurcus, Streptococcus faecalis,Escherichia coli, Pseudomonas aeruginosa or Candida albicans ) for aperiod of time of contact t (1 or 30 minutes).

The binder is poured into sterile wells and the solvent is thenevaporated off under vacuum in the hot for one week. A known number ofbacterial colonies is then placed in contact, and then a part is takenand placed in incubation for 48 hours. At this stage, the remainingcolonies are then counted.

Polymer 1: N-octyl N,N-dimethylaminopropyl methacrylamide bromide

Polymer 2: N-dodecyl N,N-dimethylaminopropyl methacrylamide bromide

Polymer 3: N-hexadecyl N,N-dimethylaminopropylmethacrylamide bromide

Polymer 4: N-octyl N,N-dimethylaminopropylmethacrylamide chloride

Polymer 5: N-dodecyl N,N-dimethylamninopropylmethacrylamide chloride

Polymer 6: N-hexadecyl N,N-dimethylaminopropylmethacrylamide chloride

Polymer 7: N-octyl N-N-dimethyl aminoethylmethacrylate bromide(47%)-methacrylate (53%) copolymer

Polymer 8: N-octyl N,N-dimethyl aminoethylmethacrylate bromide(65%)-methacrylate (45%) copolymer

The results shown in Table 1 below are those of a determination carriedout with an innoculum of Staphylococcus aureus, the initial number ofcolonies being N₀=55.10⁶.

TABLE 1 quaternary N = number of bacterial colonies poly- mass % ofammonium remaining mer quaternary content t = 30 min. Log n° ammonium(mole/kg) t = 1 min (N₃₀) (N₀/N₃₀) 1 100 2.75 0.75 · 10⁶ 100 5.7 2 1002.39 48 · 10⁶  0 7.7 3 100 2.11 3 · 10⁶  75 5.9 4 100 3.14 0.02 · 10⁶ 30 6.3 5 100 2.67 2.1 · 10⁶  23 6.4 6 100 2.32 1.1 · 10⁶  0 7.7 7  471.33 5 · 10⁶ 1.0 8  65 1.87 120 6.5

The results show that the polymers in which the quaternary ammoniumcontent is greater than 1 mole/kg possess a significant antibacterialactivity.

What is claimed is:
 1. An antimicrobial agent comprising anon-cross-linked polymer comprising a resin selected from the Groupconsisting of an ester resin, an amide resin, and an ester and amideresin, having a quaternary ammonium salt bonded thereto by a covalentbond which is potentially reactive with water, the quaternary ammoniumsalt being present in an amount of at least 1 mole/kg, and being atleast one compound selected from the group consisting of: a) a compoundof the formula

where R¹ is a C₁-C₅alkyl chain, R₂ is a C₁-C₅alkyl chain, R₃ is a C₈-C₂₀alkyl chain or an aryl or arylalkyl group, and X is an anion; and b) acompound of formula W⁺X⁻, where W⁺ is a saturated or unsaturatedheterocycle comprising a quaternized nitrogen atom substituted with asubstituent R₄ or directly bonded to the polymer, where R₄ is a C₁-C₂₀alkyl chain or an aryl or alkylaryl group, and X⁻ is an anion. 2.Non-cross-linked polymer comprising a resin selected from the groupconsisting of an ester resin, an amide resin, and an ester and amideresin, having a quaternary ammonium salt bonded thereto by a covalentbond which is potentially reactive with water, the quaternary ammoniumsalt being present in an amount of at least 1 mole/kg, the polymerhaving a general formula (II):

where W⁺ is a saturated or unsaturated heterocycle comprising aquaternized nitrogen atom substituted with a substituent R₄, or directlybonded to the polymer, and where R₄ is a C₁-C₂₀ alkyl chain or an arylor alkylaryl group, and X⁻ is an anion.
 3. Agent according to claim 1,wherein the quaternary ammonium content of the polymers is at least 2moles/kg.
 4. Agent according to claim 3, wherein when B represents anarylene or arylalkylene group and/or R₃ is an aryl or arylalkyl group,the aromatic ring is a phenyl group and the alkyl chain is a C₁-C₅ alkylchain.
 5. Agent according to claim 1, wherein characterised in that theweight percentage of quaternary ammonium salt is at least 80% of polymerweight.
 6. Agent according to claim 5, wherein the weight percentage ofquaternary ammonium salt is 100% of polymer weight.
 7. Agent accordingto claim 1, wherein the polymer is selected from the group consisting ofN-octyl N,N-dimethylaminopropylmethacrylamide bromide, N-dodecylN,Ndimethylaminopropyl methacrylamide bromide, N-hexadecylN,Ndimethylaminopropylmethacrylamide bromide, N-octylN,N-dimethylaminopropylmethacrylamide chloride, N-dodecyl N,Ndimethylaminopropylmethacrylamide chloride, N-hexadecylN,Ndimethylaminopropylmethacrylamide chloride, N-octyl N-N-dimethylaminoethylmethacrylate bromide (47%)-methacrylate (53%) copolymer, andN-octyl N,N-dimethyl aminoethylmethacrylate bromide (65%)-methacrylate(45%) copolymer.
 8. Polymer according to claim 2, wherein that theweight percentage of quaternary ammonium salts is 80% of polymer weight.9. Polymer according to claim 8, wherein that the weight percentage ofquaternary ammonium salts is 100% of polymer weight polymer.
 10. Paintcomprising at least one polymer according to claim 2, as binder. 11.Facade coating comprising at least one polymer according to claim 2, asbinder.
 12. Object having antimicrobial properties comprising a polymeraccording to claim
 2. 13. Object according to claim 12, which is amedical material.
 14. A method for preparing a self-regenerating polymercomprising utilizing a polymer according to claim
 2. 15. Agent accordingto claim 1, wherein said polymer is of general formula (I)

where A is function

and/or an amide function of formula

and R is H or CH₃, and B is a C₀-C₅ alkylene chain, which is linear orbranched, or an arylene or arylalkylene group.
 16. Polymer according toclaim 2, additionally comprising units of formula (I):

where A is function

and/or an amide function of formula

and R is H or CH₃.
 17. Polymer according to claim 2, wherein thequaternary ammonium salt is present in an amount of at least 2 moles/kg.18. Polymer according to claim 16, wherein B is an arylene orarylalkylene group and/or R₃ is an aryl or arylalkyl group, and thegroup comprises an aromatic ring which is a phenyl group, and an alkylchain which is a C₁-C₅ alkyl chain.
 19. Polymer according to claim 2,wherein the heterocycle additionally comprises at least one furtherheteroatom.
 20. Method for obtaining a polymer according to claim 2,comprising the step of reacting a monomer comprising a tertiary amine offormula:

with an alkyl halide of formula R₄X, and polymerizing the reactedmonomer.
 21. Method according to claim 20, wherein the heterocycleadditionally comprises at least one further heteroatom.
 22. Agentaccording to claim 1, wherein the heterocycle additionally comprises atleast one further heteroatom.